GWEN IFILL: Economics and the politics of immigration are expected to remain front and center throughout the campaign year.

For more on the growing immigration policy divide, I'm joined by Marielena Hincapie, executive director of the National Immigration Law Center Immigrant Justice Fund, and Josh Blackman, an associate professor at the South Texas College of Law.

Marielena Hincapie, let me ask — start by asking you what leaped out at you in watching that debate, especially the part, the immigration debate last night?

I, frankly, was initially shocked at what I was starting to hear from Trump, and then deeply, deeply troubled. It was surreal. I think many viewers may not realize that when Donald Trump was invoking President Eisenhower's immigration plan that resulted in the deportation of over a million individuals, he was actually referring to Operation Wetback.

Operation Wetback is one of the darkest and most shameful periods of our immigration history in this country, where immigrants from Mexico, including U.S. citizens of Mexican descent, were deported. That is basically — historians think of it as ethnic cleansing. That is shocking that in 2015 one of our presidential candidates is espousing that as his model for immigration.

GWEN IFILL: Josh Blackman, as you watched and listened to what they were saying, what leaped out at you?

JOSH BLACKMAN, South Texas College of Law: So, I think Marielena is correct. It's physically impossible to remove 11 million immigrants.

But I think the correct framework is that some sort of reform has to be passed and that this cannot be accomplished through executive action, which is what President Obama has done.

GWEN IFILL: So, what is it that you heard last night that sounded like a reasonable approach?

JOSH BLACKMAN: So, I think Senator Rubio advanced a proposal where immigrants who have been here for a while who have families and have not gotten in trouble, had they stayed 10 years, there will be a pathway for some sort of way for them to remain. And he also suggested that certain felons would be able to be moved primarily.

GWEN IFILL: Marielena Hincapie, this week, the Fifth Circuit Court of Appeals moved to delay, to block President Obama's plan to delay deportation for some people who are not here legally. Does this — how does this change the landscape of the immigration debate or does it?

MARIELENA HINCAPIE: Well, right now, the decision was a devastating decision, particularly for the five million U.S. citizen children whose parents would have benefited from DACA.

And it was an expected decision, so it doesn't quite change things too much, in the sense that we remain in legal status quo, legal limbo for these families. On the other hand, because the Supreme Court is likely to take this case — and we're very glad that the Obama administration immediately said that they would be appealing — this is a case of national significance which is likely to be decided just months before the 2016 election.

So I think the issue will continue to be front and center and probably increase in terms of the debates, particularly in the general election.

GWEN IFILL: Josh Blackman, does this help or hurt your election year argument?

JOSH BLACKMAN: So, I think the question is not whether the Supreme Court will hear it, but when the Supreme Court will hear it.

So, Marielena is correct.

GWEN IFILL: It's definitely going to happen?

JOSH BLACKMAN: Oh, it's definitely going to happen.

But it will either happen in May of 2016 or November of 2016. And the variable is when the court is able to grant certiorari, when it's able to grant review. And this is based first on when the U.S. government files their appeal and second when Texas files their response.

If the process too late, it's very possible that this process will be stretched and kicked until next year, so it would not even be argued until there's a new president in office.

GWEN IFILL: There were as many approaches to the immigration debate on stage last night as there were candidates.

I want to run through a few of them with you, Marielena Hincapie, starting with you.

Jeb Bush talked about fines and talking as a way of making sure that people stay — obey the law. How applicable can that be?

MARIELENA HINCAPIE: Yes, paying a penalty has actually been one of the central factors of all of the immigration reform proposals, legislative proposals in the past.

I think Jeb Bush is right that that is often — and immigrants are ready and willing to pay a fine to be able to stay in the U.S. to obtain lawful status and work lawfully and not have that fear of deportations and contribute even more to our country.

GWEN IFILL: Josh Blackman, we have heard much discussion about the path to citizenship, but a lot less discussion than we used to. People like Jeb Bush and Marco Rubio, who used to say — and even John Kasich, I think, last night suggested it — but it's being talked about a lot less. Why is that?

JOSH BLACKMAN: I think one of the factors we have to consider is the role that President Barack Obama's presidential executive actions played in chilling congressional reform.

Speaker Paul Ryan had a piece in “USA Today” last week effectively arguing that because the president acts unilaterally, it's harder to trust the president. I think, in many respects, this unilateral action has made it more difficult to actually have some sort of comprehensive immigration reform.

GWEN IFILL: You're saying it's the unilateral action, not the actual substance of the policy itself?

JOSH BLACKMAN: Well, I think any discussion of whether you're actually rewarded people perhaps who enter the country illegally must be premised on what President Obama has done previously.

If in fact the president is trying to abrogate and bypass Congress, it makes it less likely that Congress will want to work with him to move forward.

GWEN IFILL: Marielena Hincapie, some people — Ben Carson is one of the people who have suggested that perhaps a guest-worker program might be an approach. Is that something that you can see happening that is middle ground?

MARIELENA HINCAPIE: Absolutely not, not a guest-worker program by itself.

I think particularly for Ben Carson and the Republican candidates who yesterday talked about not being in support of the minimum wage, when we — when they are thinking of adding guest workers as the solution to immigration, that simply is going to depress wages and working conditions even more for U.S. workers.

We need to ensure that the 11 million people who are here who are already working have a path to citizenship and that we separately look at what are the forms, legal channels for people to come in the future.

For current guest-worker programs, they are extremely full of exploitation, mainly because workers are tied to an employer who can exploit them and unless those individual workers, those temporary workers have the same rights as U.S. workers, are able to leave that work and take their visa, have a portable visa, that guest-worker programs are just not the answer and not the solution. And it's definitely not the solution for the 11 million who are here and who are working and who have deep ties to our communities.

GWEN IFILL: Josh Blackman, what about the so-called dreamers? They got their hopes up last year with the idea that they would be able to stay here or they could at least apply to stay here. Is that going to fall apart or is that anything that any of these Republicans are supporting?

JOSH BLACKMAN: Congress defeated the DREAM Act and the president went ahead and enacted not the exact same thing, but significant portions of it, through executive action.

And I think in many respects, that, too, that has chilled the decision of whether Congress can act. And one point I make — I would like to make on the timing of the Supreme Court appeal, the Obama administration had a chance to appeal to the Supreme Court in May of 2016. Their failure to do it basically ensured that this couldn't be decided until the earliest of the summer before the election.

So whether it is in fact a priority for the Obama administration to appeal is not clear. They may be content to let this sit as a political issue and have Senator Clinton perhaps and the Republican candidate duke this out. There may be political elements here in delaying the appeal itself.

GWEN IFILL: Briefly, where is public opinion on this?

JOSH BLACKMAN: On?

GWEN IFILL: On this whole issue?

JOSH BLACKMAN: Well, I think for the most part, people are looking to have a comprehensive reform through Congress and not through unilateral executive action.

GWEN IFILL: And, Marielena, one final thought on public opinion.

MARIELENA HINCAPIE: Yes, as Joshua said, there is a lot of support. A majority of Americans support both comprehensive immigration reform through Congress, but recent polling actually shows that the majority of Americans also support the president's actions.

They don't believe that undocumented immigrants who are here, who are contributing to our economy, who have children, who have deep ties to our country should be deported either. So there is support for the president's action, as well as Congress. We — ultimately, we need Congress to act so that a future president can sign that law into — sign an immigration reform bill into law.

GWEN IFILL: Marielena Hincapie of the National Immigration Law Center and Josh Blackman of the South Texas College of law, thank you both very much.